Mechanical Behavior comparison of aircraft joints modeling

Resumo

The procedure of structural design for aircraft parts is widely known and discussed in the academy and
in the industry, although it has been improved along the time. It is based on a detailed process of aerodynamics
loads study coupled or not with specifications required by regulatory agencies. Further, several interactions of

analysis are done to define the critical stress state of the structure submitted to load conditions, because it is a com-
plex structure that needs to be often improved and updated (considering the requirement of assembly/disassembly

simplicity). There are several components in an aircraft attached to each other by the use of fasteners, rivets or nuts
made of different materials (aluminum, steel, Inconel among others). In fact, it is not to easy to obtain stress state
of the aeronautical structure for real loading conditions. Further, it is also difficult to calculate the load acting on
each one of the joints. Several studies were already performed in order to obtain the correct understanding of how
actual loads is distributed through the joints. The present work aims to compare results in aircraft joints (focusing
in spar and skin regions), considering three levels of fidelity to understand the differences in the structural response
using different type of modeling approach. Finite Element Analysis modelings made using Nastran software were
performed. Preliminary results show good response agreement even for high and intermediate detail levels. Low
detail level present promisor response as a tool for predesign.